1. Field of Invention
The present invention relates to a projector which includes a light source, an electro-optical device for forming an optical image by a light emitted from the light source according to image information, a projection lens for enlarging and projecting the image formed by the electro-optical device, a fan for drawing external air into the main body or for exhausting air inside the main body to the outside, and a housing for covering the main body.
2. Description of Related Art
Hitherto, a projector has been known which includes a light source unit having a light source, an electro-optical device for forming an optical image by a light emitted from the light source according to image information, and a projection lens for enlarging and projecting the image formed by the electro-optical device. Such a projector have been widely used for multimedia presentations at conferences, academic meetings, exhibitions, and the like.
While the projector is sometimes kept installed in a conference room or the like for a presentation, it is sometimes brought in as necessary, or is stored in another place after use. Therefore, a reduction in size of the projector is promoted to facilitate transportation. In addition, in order to improve visibility of the image displayed by the projector, an increase in brightness of the light source is facilitated.
In such a projector in which a reduction in size and an increase in brightness of the light source are facilitated, efficient cooling of the interior of the projector is a problem from the viewpoints of dense provision of components inside the device associated with a reduction in size and the elevation in temperature inside the device associated with an increase in brightness. In particular, while the light source for emitting light is composed of an arc discharge lamp, such as a metal halide lamp or a xenon lamp, the light source most readily heats up among the components inside the device, and it is important to efficiently cool the light source. Therefore, according to a conventional projector, a fan for drawing or exhausting cooling air is disposed near the light source so as to ensure cooling of the light source by a large volume of cooling air.
On the other hand, since the light source has a finite service life, it must be replaced. Hitherto, in the operation for replacing the light source, a light source-replacement cover has been provided at a part of an outer casing, and a light source unit including the light source is removed from the device after opening the light source-replacement cover.
In the case where the light source-replacement cover is opened to remove the light source, other components must be disposed so as not to interfere with the replacement of the light source. Thus, the disposition of the components around the light source is restricted.
That is, while the above-described fan is an example of a component disposed on the periphery of the light source, it is difficult to effectively use the peripheral area around the light source as a space for disposing the components other than the light source, resulting in problems in reducing the size of the device.
In addition, when priority is given to a reduction in size of the device, other components may be disposed around the light source. In such a case, the replacement operation requires significant labor such that other components must be removed after the light source-replacement cover has been removed, and then the light source must be replaced.
It is an object of the present invention to provide a projector capable of easily replacing and efficiently cooling a light source, and capable of facilitating a reduction in size of the device.
A projector according to the present invention includes a light source, an electro-optical device for forming an optical image by a light emitted from the light source according to image information, a projection lens for enlarging and projecting the image formed by the electro-optical device, a fan for drawing external air into the main body or for exhausting air inside the main body to the outside, and an outer casing for covering the main body. The light source may be attachable to and detachable from the main body via a light source-replacement cover. The light source-replacement cover may include a part of the outer casing and may have an ventilation hole for drawing or exhausting air provided therein, and the fan integrally mounted thereto.
According to the present invention as described above, the fan that is originally disposed near the light source may be integrally mounted to the light source-replacement cover. Therefore, by only opening the light source-replacement cover, the light source can be easily attached and detached via the space formed thereby. In addition, it is not necessary to separately secure the special space for replacing the light source in the device. Therefore, other components except the fan can be disposed near the periphery of the light source, and layout efficiency can be improved to reduce the size of the device. Also, since the fan is brought near the light source as usual when the light source-replacement cover is closed, the light source can be efficiently cooled.
The light source-replacement cover may be opened and closed by being removed completely from the main body or the outer casing, or may be opened and closed by being rotatably supported by the main body or the outer casing, for example, in the foregoing projector, the light source-replacement cover may desirably be provided on the side face of the outer casing.
In order to increase the brightness of the displayed image, a plurality of projectors may be used in a stacked state. In such a case, if the light source-replacement cover is provided on the upper surface or the lower surface of the outer casing, when replacing the light source of one projector, the opening and closing of the light source-replacement cover may be disturbed by the other projector. Therefore, the stacked projectors must be separated, and the separation operation and various adjusting operations after stacking the projectors again require significant labor.
In the present invention, however, since the light source-replacement cover is provided on the side face of the outer casing, the light source-replacement cover can be opened and closed with the projectors stacked, and replacement operation of the light source can be easily performed.
In addition, in the projector of the present invention, the light source-replacement cover may preferably be formed by a heat insulating material, and the outer casing except the light source-replacement cover may preferably be made of metal.
In such a case, since the light source-replacement cover has a thermal insulating property, from the viewpoint of the handling safety, the replacement cover can be used at a section that is more likely to heat up as compared to a case where it is made of metal. For this reason, not only an intake fan but also an exhaust fan that is more likely to heat up, can be mounted to the light source-replacement cover.
On the other hand, the outer casing except the light source-replacement cover is made of metal, whereby rigidity of the overall outer casing can be improved.
Furthermore, in the projector of the present invention, a direction of insertion and extraction of a connector on the side of a power supply and a connector on the side of the light source provided in the main body may preferably be the same as a direction of attachment and detachment of the light source to and from the main body.
In such a case, the attachment and detachment of the light source and the insertion and extraction of the connectors can be effected simultaneously. Therefore, an electrical connection between the light source and the power supply can be easily and rapidly established.
In the projector of the present invention, an electric power-supplying line to the fan may preferably be electrically cut off and conducted according to opening and closing of the light source-replacement cover. That is, since the electric power-supplying line to the fan is cut off at the same time the light source-replacement cover is opened, the fan can be securely prevented from being erroneously operated during replacement operation of the light source.
In the foregoing, the fan may be provided with a fan guard on the opposite side of the light source-replacement cover, whereby the safety during the replacement operation of the light source (in particular, during the opening and closing of the light source-replacement cover) is improved.